The use of inhalation devices in the administration of medicaments, for example in bronchodilation therapy is well known. Such devices generally comprise a body or housing within which a medicament carrier is located. Known inhalation devices include those in which the medicament carrier is a blister strip containing a number of discrete doses of powdered medicament. Such devices usually contain a mechanism for accessing these doses, usually comprising either piercing means or means to peel the lid sheet away from the base sheet. The powdered medicament can then be accessed and inhaled.
It is an object of the present invention to provide a medicament dispenser (e.g. an inhalation device) which is refillable by insertion of a replacement cassette containing a medicament carrier. The cassette may be replaced when the medicament carrier is empty. The dispenser is therefore ‘environmentally friendly’ as the majority of the dispenser may be retained and is not disposable. It also allows the retained part of the dispenser to be fitted with additional features such as electronics which may not be cost effective on a completely disposable dispenser.
It is a further object of the present invention that the cassette may be easily removed and that a new replacement cassette can be easily inserted. It is also desirable that the operation of the medicament dispenser is straightforward and non-complex and in particular that the number of separate steps involved in preparing the dispenser for use is minimised. It is further desirable that in exceptional circumstances the cassette may be used on its own as a standalone medicament delivery system. This is especially relevant where the dispenser is designed for use in the delivery of medicament in emergency or rescue situations (e.g. asthma attacks) where simplicity and ease of use is paramount.
When not in use it is desirable from a hygiene standpoint that the dispensing part (e.g. an outlet, perhaps in the form of a mouthpiece) is provided with some kind of protective cover. The cover desirably acts both to prevent build-up of dirt on the dispensing part and to prevent ingress of dirt into the body of the dispenser through the dispensing part, which might then be subject to ingress by a patient. It is also desirable that the cover is in some way attached or mounted to the dispenser to minimise the risk that the cover is misplaced or lost. It is therefore a further object of the present invention for the body of the dispenser to act as a cover for the dispensing part when the dispenser is in storage and that the cassette is movable relative to the body to enable the dispensing part to be uncovered for use by the patient.
It is a further object of the invention to provide a medicament dispenser suitable for use with a large number of discrete doses but which is of an acceptable size for use by patients.